Combination guide and latch roller



F. ODENDHAL" 3,318,048

May 9, 1967 COMBINATION GUIDE AND LATCH ROLLER 4 SheetS-Shefet l Filed May 27, 1965 May 97 1967 F. ODENDHAL.

COMBINATION GUIDE AND LATCH ROLLER Filed May 27, 1965 4 SheeLs-Sheel 2 INVENTOR Z8) fairy/vf @of/v0 'ff/u Z0 L24 Z4. @2% 9,/

ATTORNEYS May 9, 1967 F- ODENDHAL 3,318,048

COMBINATION GUIDE AND LATCH ROLLER Filed May 27, 1965 4 Sheets-Sheet 3 INVENTOR /zowra/vf @Af/va Zou Bmmjw ATTORNEY F. CDENDHAL May 9, 1967 COMBINATION GUIDE AND LATCH ROLLER 4 Sheets-Sheet 4 Filed May 27, 1965 w 4% f ATTORNMYS United States Patent O 3,318,048 CGMBINATION GUIDE AND LATCH ROLLER Fortune Gdendhal, Hagerstown, Md., assgnor to Jamison Cold Storage Door Company, Hagerstown, Md., a company of Maryland Filed May 27, 1965, Ser. No. 459,348 4 Claims. (Cl. t9-223) This invention relates to sliding doors and more particularly to sliding doors adapted to be moved to closed, sealing positions. Such doors are 'adapted for use in cold storage compartments or for any compartment requiring a sealed closure.

In the usual sliding door construction, there is provided a mounting means for hanging the door against a Wall having a rectangular opening which is to be covered by the door. The mounting means most often includes lan overhead rail or track which is .attached to the Wall and positioned horizontally over the door opening itself. The overhead rail necessarily extends beyond the limits of lthe door opening in order that the door may be mounted for sliding movement along the rail to positions that open and close the doorway, as desired. In the usual construction, the door is suspended from the rail by means of rollers which are attached to the door and which ride on the rail. Such overhead rail systems for hanging doors are well known in the art, and an example of such a construction is shown in Mandeville Patent 1,452,306, Apr. 17, 1923. Additionally, it is a common practice to provide sealing gaskets around the perimeters of sliding doors, where they are to be used on cold storage rooms, so that a good seal may be effected when the doors are moved to closed positions. In order to assure a tight seal along the bottom margin of a door, it has lbeen a common practice to provide guide rollers mounted along the floor at the bottom edge of the door, and these guide `rollers are so spaced from the wall portions immediately adjacent 'the doorway that the sliding door is held tightly against the wall as it moves between the floor-mounted guide rollers and the wall. It is possible with the overhead rail system of hanging a door for the bottom edge of the door to swing outwardly away from the Wall while it is being moved from one position to another; therefore, it is common in the prior art construction to mount the guide rollers on the oor near .the side margin of the doorway where the leading edge of the door will pass when it is moved from a fully open position to a closed position. As the door is closed, the leading edge of the door is manually guided between the Hoormoun-ted guide roller and the Wall at the side margin of the doorway, and the door is thereby held tightly against the wall for the remainder of its movement -to a fully closed and sealed position.

The prior art mounting of a door for sliding along a wall, as just described, has certain disadvantages. The door-mounted roller is necessarily mounted near the side margin of the door opening in order to wedge the door against the wall during the complete travel of the door to its closed position. This position of the floor-mounted roller is inconvenient, and it is not unusual for the roller to be struck land damaged by carelessly driven trucks or other carriers which may be driven through such doorways. In addition, the position of the guide roller on the floor causes an accumulation of dirt in and around the guide roller, and this is a particular disadvantage in food storage compartments where high standards of sanitation are desirable.

The major disadvantage in holding a sliding door in tight engagement against a wall by a xed roller means or other wedging device is that -the gasket seals around the margins of the door are scraped during all movement of the door past the doorway opening. As soon as the leading edge of the door is wedged between the roller and vthe wall area surrounding the door opening, there is a frictional contact of all of the marginal sealing gaskets of the door against the Wall, and this contact causes the sealing gaskets to be scraped and abraded as the door is moved to its nal closed position.

The present invention provides for an improved mounting means for sliding doors whereby a tighter seal may be effected when the door is closed, and the sliding door may be moved without scraping or abr-ading the sealing means used on the door. In addition, the mounting means of `the invention maintains the sliding door in a normal upright position at all times while it is being moved, thus eliminating the inconvenience and hazard of a door swinging outwardly away from the wall at its bottom edge.

The mounting means of this invention includes the usual overhead rail suspension means for a sliding door, and this suspension means includes an inclined rail and door mounted rollers which ride on the rail. The inclination of the overhead rail is such that the sliding door is lifted upwardly away from the floor as i-t is moved from a closed to an open position, and this movement protects a bottom sealing strip of the door from rubbing on the floor below the door. In addition, the invention provides a guide rail for holding the sliding door away from -an adjoining wall when the door is moved from its fully closed position to an open position. The guide rail is located on the wall nex-t to the doorway and is easily mounted on existing structures. When the door is opened, it is spaced away from the wall for a fixed distance, as determined by the guide rail, and this carries the sealing gaskets around the door away from any frictional contact with the wall adjoining the doorway. As .a result there is no abrading of the sealing gaskets while the door is be- .ing moved along the wall. When the door is brought to a completely closed position, .a latching-means permits the door .to be drawn toward the doorway so as to effect a tight sealing of the door laround its perimeter. lIn the preferred form of this invention, .the latching means is mounted on an edge of the sliding door, and as will be seen in the more detailed discussion, the latching means also provides an engagement means for guiding the door along the guide rail when it is moved from its fully closed position to any open position.

The latching means of this invention includes spring biased rollers which are actuated to one of two positions. The position of one roller as related to the guide rail determines whether the door itself is pulled tightly against the doorway or is pushed a fixed distance away from the doorway. The latching means moves to a -rst position which pulls the door tightly toward the door opening only when the sliding door has reached a position of fully covering the doorway. In all of the open positions of the door, as related to the doorway, the latching means is actuated to a second position. The second position of the latching means provides for an engagement of a roller with a portion of the mde rail so as to guide the door a spaced distance away from the adjoining wall of the building. In addition, the roller which is engaging the guide rail serves to prevent the sliding door from swinging away from the wall for all open positions of the door. Thus, the latchin g means and its roller, which engages the guide rail, assures a spacing of the door away from the wall when the door is being opened, and, at the same time, the door is retained in its guided path adjacent the guide rail so as to not swing outwardly away from the wall.

The latching and guiding means, as defined by this invention, eliminates the usual requirement for a floor- -mounted roller near the edge of a doorway, and this eliminates the disadvantages of such a floor-mounted roller as discussed above. This invention also provides for a better sealing of the margins of a door when the door is` brought to its fully closed position. In all open positions the door is moved away from the adjoining wall so as to prevent an abrading or scaping of the gasket material or of the sealing means used around the edges of the door.

Other advantages of the sliding door an-d its latching and guiding means will become apparent in the more detailed discussion of an illustrative embodiment of the invention which follows, and in that discussion reference will be made to the accompanying drawings in which:

FIGURE 1 is a front elevation showing a sliding door in a closed position, and showing the guide means and latching means of this invention;

FIGURE 2 is a top sectional view of FIGURE l taken at a horizontal level midway up the door of FIGURE 1;

FIGURE 3 is a vertical end view of the sliding door showing the overhead track and wedging devices associated with the door;

FIGURE 4 is a cross-sectional elevation of the guide means used with this invention;

FIGURE 5 is a detailed top view of the preferred latching and guiding means of this invention shown for a closed position of the sliding door;

FIGURE 6 is ya top detailed view similar to FIGURE 5 and showing a preferred latching and guiding means for an open position of the door;

FIGURE 7 is a front view showing double spring mountings for a latching and engaging means;

FIGURE 8 is a front view similar to FIGURE 7 and showing a single spring mounting for the latching and engaging means;

FIGURE 9 is a detailed view showing an alternative form of engaging means; and

FIGURE 10 is a partial front elevation of a sliding door illustrating an alternative overhead track construction for supporting the door.

Referring to FIGURE 1, a sliding door 10' is mounted by rollers 12 on an overhead rail 14 for edgewise movement relative to a wall 16. The wall 16 includes a rectangular door opening 18 which can be covered and sealed by the sliding door 1i). The wall 16 and the door opening therethrough are in a common plane, and the door 10 is mounted to slide in a plane which is essentially parallel to the plane of the wall. The wall may be a part -of a refrigerator compartment, or other room which requires a door closure to effectively seal the room from an outside atmosphere -or temperature. The overhead rail 14 and mounting means associated therewith is conventional, and it is preferred that the overhead rail 14 be slightly inclined upwardly from a horizontal position so that the door 10 will be raised away from the oor 20 as it is moved from a closed position to an open position. The door 10 may be of any suitable construction and is preferably constructed from materials which provide it with insulation characteristics. A handle 22, 0r other means, is provided for manually sliding the door to various positions along the overhead rail 14 from which it is suspended. As shown in FIGURES 2 and 3, sealing strips or gaskets 24 are placed around the perimeter of the door to effect a sealing relationship of the door to the door opening when in a fully closed position. The sealing strips are placed on a back face 26 of the door at top and side margins which are adjacent to the wall portions surrounding the door opening. In addition, strips are placed along a bottom edge 28 of the door to maintain a seal between the door and the floor when the door is in a fully closed position.

The Xguide means of this invention is shown generally at 30 and is preferably in the form of a bar or rail which can be affixed to a portion of the wall 16 which adjoins the door opening 18. The guide means 30 includes a rail 32 which may be formed by turning down a flange along an outward extension of the guide means. As shown in FIGURE 4, the guide means has a cross-sectional conguration which approaches that of the letter Z, and one leg of the Z is attached to the wall, while the other leg forms the downturned guide rail 32 spaced outwardly from the wall. An upright flange 34 is aixed directly to the vertical wall 16, and an outwardly extending portion 36 carries along its 4outer edge the downturned rail 32. The rail is adapted to guide a roller or other engaging means within the tra-ck provided by the entire guide means 3l). The guide means 30 is mounted parallel to and spaced downwardly from the overhead rail 14. Where the overhead rail 14 is slightly inclined t-o raise the door 10 at it is moved from a closed to an open position, the guide means 30 is placed at the same inclination as the overhead rail 14.

The door 10 carries suitable engaging means for holding and guiding the door along the guide rail 32. The engaging means is shown generally at 3S and includes a roller which is held between the downturned portion 32 and the wall 16 to which the guide rail is secured. As shown in FIGURES 1 and 2, the engaging means 38 is preferably attached to an edge of the door 10, and is placed on that edge so as to properly engage the guide rail for all positions of the door.

The engaging means 38 is a special feature of this invention, and functions to move the entire door outwardly away from its sealed position when the door is moved from a fully closed position to any open position. Also, the engaging means provides a retaining function which prevents the door from swinging outwardly from the wall beyond a limited distance as determined by the position of the guide rail. In addition to the engaging means 38, a latching means is carried by the door for the purpose of returning the door to a sealed position against the perimeter of the door opening when the door is moved to a closed position. The latching means may be a separate device carried by the door, but in the preferred form of this invention, the latching means is combined with the engaging means. The two devices function automatically in response to the position of the door relative to the door opening. As shown in FIGURE 2, the door -Itl is suspended so as to be placeable, in its closed position, against frame elements 42 which are placed at the upright margins of the doorway. In addition, a frame element 43 is provided as a header across the top margin of the doorway, thereby completing a door frame having a common plane. In its fully closed position, the door 10 is brought into a tight sealing engagement with the frame elements. The placement of the door against the frame elements is determined by the latching means mentioned above, and also by wedging devices carried around the margins of the door. For eX- ample, a wedging means 44 is mounted on a face of the doorway to receive a wedge shaped element 46 carried by an edge of the door 10i In a fully closed position, the wedge element 46 is forced between the roller 48 of the wedging means and the frame 42 of the doorway. As a result, the door is wedged toward the door opening along the edge where the Wedge 46 is carried. The top edge of the door 10 is also forced against the door frame by means of a wedge plate 50 which can be seen in FIG- URES 1 and 3. This wedge plate receives an upright member S2 carried at the upper edge of the door 1()` so as to be received within the wedge plate 50' when the door is moved to its fully closed position.

The latching means is carried on an opposite upright edge of the door from the wedging means 44 and provides for a movement of that edge of the door toward the door opening. The action of the latching mechanism which is combined with the engaging means 38 will be described in greater detail below. It will be appreciated that when the door is fully closed, the gasket members 24 are pressed against the frame elements 42 and 43 so as to effectively seal the door opening with the door.

The engagement means 38` serves to move the door outwardly away from the plane of the door frame for al1 open positions of the door. The purpose of this movement is to move the sealing gaskets 24 outwardly away from any frictional contact with the door frame or any portions of the wall 16 adjoining the door opening. As can be seen in FIGURE 2, the outward extension 36 of the guide r-ail 32 extends outwardly from the wall 16 for a suicient distance to align the engaging means with the door frame. The engaging means includes a roller 54 which is guided along the inner surface of the downturned guide rail 32. The roller 54 is mounted on the engaging means and the door edge So as to be movable to one of two positions. In FIGURE 6, the roller 54 is shown in a position which permits a latching movement of the door toward the door opening when it is fully closed so as to lbe sealed against the door frame, as shown in FIGURE 5. A second position of the engaging roller 54 forces the door outwardly away from the planes of the door frame and wall so as to break the sealing engagement, as shown in FIGURE 6. The roller 54 as carried by a connecting arm 56 maintains this outward spacing of the door 10r away from the wall for all open positions of the door. In addition, the roller 54 and its connecting arm 56 prevent a swinging movement of the door outwardly beyond the predetermined space to which the door is moved by the second position of the engaging means.

A preferred form of combined engagement and latching means 38 is shown in FIGURES 5 and 6 with two positions for the engagement means `being illustrated by the separate figures. The engagement means is spring mounted on a carrier member 58 so as to be actuated to one of two positions as determined by the relationship and tension of a spring relative to the position of the engaging roller 54. The carrier member 58 may be formed from a suitable material such as a metal which is cast into the form shown, and the carrier member 58 includes a flat base portion 60 which is affixed to an upright edge of the sliding door. The base member 60 is formed to include openings 62 for receiving bolts or other fastening devices which may 'be used to secure Vthe entire carrier with its engaging means to a fixed position on the door edge. As viewed in FIGURES 5 and 6, the carrier member 58 includes an outwardly extending portion 64 which is formed integrally with the base portion 60. The outwardly extending portion 64 is designed to extend the carrier outwardly from the edge of a door so as to place the engaging roller 54 in a position for being guided along the guide rail 32. The engagement roller means 54 is mounted for pivotal movement on `the end portion 66 of the outward extension. The pivotal movement is provided by the cross pin 68 which carries the engaging means 38 ,on the end portion 66..r In the preferred form of the invention, two identical outwardly extending portions 64 are spaced from one another so as to receive the connecting arm 56 between the extensions as mounted on a cross pin 68. The connecting arm 56 carries two rollers 54 and 72, and the relative positions of the rollers as related to the door and guide rail is determined by the pivotal position of the connecting arm as carried on the carrier member 58. The connecting arm includes a spring means 74 which assists in placing the roller members in'one of the two positions. In the closed position of the door as shown` in FIGURE 5,

" the engagement roller 54 is placed against the inner surface of the guide rail --32 so as to roll along that inner surface when the door is moved in an edgewise direction. In this same position, the roller 72 is in `a first position close to the plane of the wall so as to place the closed door against the door frame members 42 and 43. comparing FIGUR-E 5 to FIGURE 6, it will be seen that the roller 72 is spaced laterally away from the plane of the wal-l for a greater distance in the FIGURE 6 position than is shown in the FIGURE 5 position. In the open position for the idoor as shown in FIGURE 6, the roller 72 acts to guide the outwardly spaced door along the ByV outer surface of the guide rail, and as will be described later, this roller further functions to actuate the door to one or the other of its two possible positions in response to the position of the door 16 relative to the door opening. The spring member '74 is mounted on a telescopingconnecting bolt 76 which links the connecting arm 56 to the base portion `66 of the carrier member 58. The telescoping bolt includes an outer tubular member 78 and inner rod mem'ber 80 which is fitted for reciprocal movement within the outer tubular member. "I he outer tubular member 78 is pivotally connected at 82 to the connecting arm 56, and lthe inner rod member 80 is pivotally connected at `84 to the base member 60. Thus, when the connecting arm 56 and its rollers 54 and 72 are moved to different positions, the telescoping Ibolt will extend or contract to accommodate the varying distances between the pivotal points 82 and 84. Additionally the coiled spring 74 which is secured at its terminal ends to the outer tubular member 78 and the rod member 80 will lessen its spring 4tension in accordance with increased lengthening of the bolt '76. In the FIGURE 5 and 6 embodiments, there is an ever present tendency of the spring means 74 to push the connecting arm 56 toward its innermost position relative to the carrier 58 as shown in FIGURE 5. Whe-n the connecting arm is in its FIG- URE 6 positions for moving the door outwardly away from a wall, it can be seen that the pivot point 82 never goes over a center line drawn between the pivots 68 and 84. A stop member 86 is formed integrally with the outwardly extending portions 64 so as to prevent the pivot 82 from going past the center line drawn between the other points 68 and 84. Accordingly, in the FIGURE 6 position, there is a force exerted by the spring member 74 toward the pivot point 82 which is suicient to displace the connecting arm 56 toward its FIGURE 5 position when the door is brought to a fully closed position. However, for all open positions of the sliding door, the roller 72 is prevented from being displaced because of its abutting engagement with the outer surface of the guide rail 32. Because of the pressure of the spring 74, the roller 72 has a tendency to press toward the outer surface of the guide rail 32, and this force coupled with the pressure of the roller 54 against the inner surface of guide rail 32 results in a positive engagement of the two rollers against the guide rail throughout their travel along the rail. When Ithe door is -moved to a completely closed position, the roller 54 is actuated to the position shown in FIGURE 5. For all open positions of the door, the roller 72 is prevented from moving toward the wall by the presence of the guide rail interposed `between the roller 72 and the wall. However, in the fully closed position of the door, the roller 72 is no longer in contact with the guide rail because the guide rail is terminated so as to Ileave a gap within which the roller 72 may move when the door is fully closed. This gap is shown in the form of a slot 88 in FIGURES 1 and 2, and the slot 88 maybe formed in one of the frame elements 42 by any suitable mean-s. When the roller 72 is actuated to the position shown in FIGURE 5, it will be appreciated that the roller 54 is pressed against the inner surface of the guide rail with suflicient force to pull the door laterally toward the door opening, and this provides a tight sealing of the door against the door frame for the fully closed position of the door. As the door is initially moved in an edgewise plane from a fully closed position to any open position, the roller 72 is caused to ride out of the slot 88 on the inclined surface 89- and to take its position on the outside surface of the guide rail 32. This outward movement of the roller 72 causes the door to `be pushed outwardly away from the wall so that the door fully clears the wall for all open positions. In this manner, the sealing strips normally associated with the door are abruptly moved out of sealing engagement with the door `frame as soon as the door is initially moved from its fully closed position, and there is no frictional sliding engagement of the sealing means for any portion of travel of the sliding door.

FIGURES 7 and 8 show side views of the carrier memer 58 with the installed connecting arm and engaging rollers. FIGURE 7 shows a carrier member having accommodation for two spring-loaded telescoping bolts 76 held in position by the pins 82 and 84. FIGURE 8 shows a carrier member having a single spring-loaded telescoping bolt, and it should be noted that both forms of construction utilize the same casting construction for the carrier member 53.

An alternative form of engaging means is shown in FIGURE 9, and the main difference in this engaging means as compared to the embodiment of FIGURES and 6, resides in the over center position which the springloaded bolt takes when the rollers are in the relative positions of FIGURE 6. In the FIGURE 9 embodiment, there is no stop member 86 and the pivotal connector 82 can move past a center line drawn between the pivot points 68 and 34, as shown by the dotted-line position for the bolt 76. This results in a snap action of the rollers S4 and 72 into their various positions, and such an alternative form of engaging means may be desired where it is preferred to move the rollers quickly to one of their two possible positions. However, the preferred embodiment, as shown in FIGURES 5 and 6, has the advantage in maintaining a pressure of the two rollers 54 and 72 against opposite faces of the guide rail, and this maintains the door in a more stable relationship to the guide rail and to the wall as it is being moved to its various positions. In the construction shown in FIGURE 9, the door would likewise be prevented from swinging outwardly for any great distance away from the guide rail by the engagement of roller 54 with the inner surface of that rail; however, there would be a certain amount of lateral movement of the door for the distance defined by the space between the rollers 54 and 72 as related to the guide rail passing between those rollers.

Referring to FIGURE 10, the overhead track system may be constructed with dips in the track as indicated generally at 90. Such a construction causes the door 10 to be lifted upwardly as it is moved from a closed to an open position, and this takes the bottom sealing gaskets 24 out of Contact with the oor and protects the gaskets from any abrading action for the entire movement of the door. When the door is closed, it can be seen that the overhead rollers 12 each reach inclined portions 90 of the overhead rail simultaneously so that the entire door is dropped into a sealing position. In this manner, the door is abruptly moved away from the wall by the latching means described above, and also abruptly moved away from the floor by the overhead track means shown in FIGURE 10, and none of the sealing strips around the perimeter of the door frictionally engage any part of the wall or the floor during movements of the door.

Although this invention has been described with reference to preferred embodiments of the door guide and latching means combination, changes in construction will be apparent to those skilled in the art, and such changes are intended to be included within the scope of the invention as set forth in the appended claims.

What I claim is:

l. In the combination of a wall having a door opening; a door for covering the opening, and a substantially horizontal'overhead mounting means on said wall for suspending the door for horizontal sliding movements relative to the door opening, whereby the door opening may be opened and closed by sliding movements of said door, the improvement comprising:

a guide means mounted on a wall portion adjoining said door opening and at a position spaced downwardly from and parallel to said overhead mounting means said guide means including a track portion projecting outwardly from said wall,

engagement means carried by said door for riding along said track portion of the guide means, said engagement means having two separate members for contacting and engaging opposed vertical surfaces of said track portion, whereby said door is positively maintained in a position outwardly from the wall in all open positions, said engagement meansl further including means for moving said door toward the wall when said door is moved to its closed position.

2. The combination of claim 1 wherein said engagement means and said last named means are included in a single unit which is mounted on an edge of said door, said unit further having two separate roller means which function as said separate members for contacting and engaging opposed surfaces of the track portion of the guide means, said roller means being spaced from one another by a xed distance and being actuatable to one of two positions, a first position for moving said door toward the doorway in its fully closed position for sealing the door relative to the doorway, and a second position for guiding and maintaining the door in a position outwardly away from the wall.

3. T he combination of claim 2 wherein said single unit is pivotally mounted relative to said door edge for moving the pair of roller members into and out of the two positions, said single unit and the roller members carried thereby being spring biased toward the wall and doorway, and including:

a recess adjacent to said doorway for receiving one of said roller members into the recess when the door reaches a position which covers said doorway, whereby the spring biased unit causes one of the roller members to enter said recess and to draw the door toward the doorway in a sealing relationship.

4. The combination of claim 3 wherein said pivotally mounted unit is tripped into said second position when said door is moved out of a fully closed position, whereby the roller member which is placeable into said recess is moved into contacting relationship with said track portion so as to engage an opposite surface of said track portion from a surface engaged by the second roller member of the pair.

References Cited by the Examiner UNITED STATES PATENTS 1,603,666 10/1926 Dodge 49-221 1,604,099 10/ 1926 Johnson 49-449 1,779,752 10/ 1930 Rassier 49-209 FOREIGN PATENTS 1,325,477 3/1963 France.

DAVID I. WILLIAMOWSKY, Prima/"y Examiner.

KENNETH DOWNEY, Examiner, 

1. IN THE COMBINATION OF A WALL HAVING A DOOR OPENING; A DOOR FOR COVERING THE OPENING, AND A SUBSTANTIALLY HORIZONTAL OVERHEAD MOUNTING MEANS ON SAID WALL FOR SUSPENDING THE DOOR FOR HORIZONTAL SLIDING MOVEMENTS RELATIVE TO THE DOOR OPENING, WHEREBY THE DOOR OPENING MAY BE OPENED AND CLOSED BY SLIDING MOVEMENTS OF SAID DOOR, THE IMPROVEMENT COMPRISING: A GUIDE MEANS MOUNTED ON A WALL PORTION ADJOINING SAID DOOR OPENING AND AT A POSITION SPACED DOWNWARDLY FROM AND PARALLEL TO SAID OVERHEAD MOUNTING MEANS SAID GUIDE MEANS INCLUDING A TRACK PORTION PROJECTING OUTWARDLY FROM SAID WALL, ENGAGEMENT MEANS CARRIED BY SAID DOOR FOR RIDING ALONG SAID TRACK PORTION OF THE GUIDE MEANS, SAID ENGAGEMENT MEANS HAVING TWO SEPARATE MEMBERS FOR CONTACTING AND ENGAGING OPPOSED VERTICAL SURFACES OF SAID TRACK PORTION, WHEREBY SAID DOOR IS POSITIVELY MAINTAINED IN A POSITION OUTWARDLY FROM THE WALL IN ALL OPEN POSITIONS, SAID ENGAGEMENT MEANS FURTHER INCLUDING MEANS FOR MOVING SAID DOOR TOWARD THE WALL WHEN SAID DOOR IS MOVED TO ITS CLOSED POSITION. 